drivers/media/dvb/b2c2/flexcop-i2c.c

   1 /*
   2  * This file is part of linux driver the digital TV devices equipped with B2C2 FlexcopII(b)/III
   3  *
   4  * flexcop-i2c.c - flexcop internal 2Wire bus (I2C) and dvb i2c initialization
   5  *
   6  * see flexcop.c for copyright information.
   7  */
   8 #include "flexcop.h"
   9
  10 #define FC_MAX_I2C_RETRIES 100000
  11
  12 /* #define DUMP_I2C_MESSAGES */
  13
  14 static int flexcop_i2c_operation(struct flexcop_device *fc, flexcop_ibi_value *r100)
  15 {
  16         int i;
  17         flexcop_ibi_value r;
  18
  19         r100->tw_sm_c_100.working_start = 1;
  20         deb_i2c("r100 before: %08x\n",r100->raw);
  21
  22         fc->write_ibi_reg(fc, tw_sm_c_100, ibi_zero);
  23         fc->write_ibi_reg(fc, tw_sm_c_100, *r100); /* initiating i2c operation */
  24
  25         for (i = 0; i < FC_MAX_I2C_RETRIES; i++) {
  26                 r = fc->read_ibi_reg(fc, tw_sm_c_100);
  27
  28                 if (!r.tw_sm_c_100.no_base_addr_ack_error) {
  29                         if (r.tw_sm_c_100.st_done) {  /* && !r.tw_sm_c_100.working_start */
  30                                 *r100 = r;
  31                                 deb_i2c("i2c success\n");
  32                                 return 0;
  33                         }
  34                 } else {
  35                         deb_i2c("suffering from an i2c ack_error\n");
  36                         return -EREMOTEIO;
  37                 }
  38         }
  39         deb_i2c("tried %d times i2c operation, never finished or too many ack errors.\n",i);
  40         return -EREMOTEIO;
  41 }
  42
  43 static int flexcop_i2c_read4(struct flexcop_i2c_adapter *i2c,
  44         flexcop_ibi_value r100, u8 *buf)
  45 {
  46         flexcop_ibi_value r104;
  47         int len = r100.tw_sm_c_100.total_bytes, /* remember total_bytes is buflen-1 */
  48                 ret;
  49
  50         /* work-around to have CableStar2 and SkyStar2 rev 2.7 work
  51          * correctly:
  52          *
  53          * the ITD1000 is behind an i2c-gate which closes automatically
  54          * after an i2c-transaction the STV0297 needs 2 consecutive reads
  55          * one with no_base_addr = 0 and one with 1
  56          *
  57          * those two work-arounds are conflictin: we check for the card
  58          * type, it is set when probing the ITD1000 */
  59         if (i2c->fc->dev_type == FC_SKY_REV27)
  60                 r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
  61
  62         ret = flexcop_i2c_operation(i2c->fc, &r100);
  63         if (ret != 0) {
  64                 deb_i2c("Retrying operation\n");
  65                 r100.tw_sm_c_100.no_base_addr_ack_error = i2c->no_base_addr;
  66                 ret = flexcop_i2c_operation(i2c->fc, &r100);
  67         }
  68         if (ret != 0) {
  69                 deb_i2c("read failed. %d\n", ret);
  70                 return ret;
  71         }
  72
  73         buf[0] = r100.tw_sm_c_100.data1_reg;
  74
  75         if (len > 0) {
  76                 r104 = i2c->fc->read_ibi_reg(i2c->fc, tw_sm_c_104);
  77                 deb_i2c("read: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
  78
  79                 /* there is at least one more byte, otherwise we wouldn't be here */
  80                 buf[1] = r104.tw_sm_c_104.data2_reg;
  81                 if (len > 1) buf[2] = r104.tw_sm_c_104.data3_reg;
  82                 if (len > 2) buf[3] = r104.tw_sm_c_104.data4_reg;
  83         }
  84
  85         return 0;
  86 }
  87
  88 static int flexcop_i2c_write4(struct flexcop_device *fc, flexcop_ibi_value r100, u8 *buf)
  89 {
  90         flexcop_ibi_value r104;
  91         int len = r100.tw_sm_c_100.total_bytes; /* remember total_bytes is buflen-1 */
  92         r104.raw = 0;
  93
  94         /* there is at least one byte, otherwise we wouldn't be here */
  95         r100.tw_sm_c_100.data1_reg = buf[0];
  96
  97         r104.tw_sm_c_104.data2_reg = len > 0 ? buf[1] : 0;
  98         r104.tw_sm_c_104.data3_reg = len > 1 ? buf[2] : 0;
  99         r104.tw_sm_c_104.data4_reg = len > 2 ? buf[3] : 0;
 100
 101         deb_i2c("write: r100: %08x, r104: %08x\n", r100.raw, r104.raw);
 102
 103         /* write the additional i2c data before doing the actual i2c operation */
 104         fc->write_ibi_reg(fc, tw_sm_c_104, r104);
 105         return flexcop_i2c_operation(fc, &r100);
 106 }
 107
 108 int flexcop_i2c_request(struct flexcop_i2c_adapter *i2c,
 109         flexcop_access_op_t op, u8 chipaddr, u8 addr, u8 *buf, u16 len)
 110 {
 111         int ret;
 112
 113 #ifdef DUMP_I2C_MESSAGES
 114         int i;
 115 #endif
 116
 117         u16 bytes_to_transfer;
 118         flexcop_ibi_value r100;
 119
 120         deb_i2c("op = %d\n",op);
 121         r100.raw = 0;
 122         r100.tw_sm_c_100.chipaddr = chipaddr;
 123         r100.tw_sm_c_100.twoWS_rw = op;
 124         r100.tw_sm_c_100.twoWS_port_reg = i2c->port;
 125
 126 #ifdef DUMP_I2C_MESSAGES
 127         printk(KERN_DEBUG "%d ", i2c->port);
 128         if (op == FC_READ)
 129                 printk("rd(");
 130         else
 131                 printk("wr(");
 132
 133         printk("%02x): %02x ", chipaddr, addr);
 134 #endif
 135
 136         /* in that case addr is the only value ->
 137          * we write it twice as baseaddr and val0
 138          * BBTI is doing it like that for ISL6421 at least */
 139         if (i2c->no_base_addr && len == 0 && op == FC_WRITE) {
 140                 buf = &addr;
 141                 len = 1;
 142         }
 143
 144         while (len != 0) {
 145                 bytes_to_transfer = len > 4 ? 4 : len;
 146
 147                 r100.tw_sm_c_100.total_bytes = bytes_to_transfer - 1;
 148                 r100.tw_sm_c_100.baseaddr = addr;
 149
 150                 if (op == FC_READ)
 151                         ret = flexcop_i2c_read4(i2c, r100, buf);
 152                 else
 153                         ret = flexcop_i2c_write4(i2c->fc, r100, buf);
 154
 155 #ifdef DUMP_I2C_MESSAGES
 156                 for (i = 0; i < bytes_to_transfer; i++)
 157                         printk("%02x ", buf[i]);
 158 #endif
 159
 160                 if (ret < 0)
 161                         return ret;
 162
 163                 buf  += bytes_to_transfer;
 164                 addr += bytes_to_transfer;
 165                 len  -= bytes_to_transfer;
 166         }
 167
 168 #ifdef DUMP_I2C_MESSAGES
 169         printk("\n");
 170 #endif
 171
 172         return 0;
 173 }
 174 /* exported for PCI i2c */
 175 EXPORT_SYMBOL(flexcop_i2c_request);
 176
 177 /* master xfer callback for demodulator */
 178 static int flexcop_master_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int num)
 179 {
 180         struct flexcop_i2c_adapter *i2c = i2c_get_adapdata(i2c_adap);
 181         int i, ret = 0;
 182
 183         /* Some drivers use 1 byte or 0 byte reads as probes, which this
 184          * driver doesn't support.  These probes will always fail, so this
 185          * hack makes them always succeed.  If one knew how, it would of
 186          * course be better to actually do the read.  */
 187         if (num == 1 && msgs[0].flags == I2C_M_RD && msgs[0].len <= 1)
 188                 return 1;
 189
 190         if (mutex_lock_interruptible(&i2c->fc->i2c_mutex))
 191                 return -ERESTARTSYS;
 192
 193         for (i = 0; i < num; i++) {
 194                 /* reading */
 195                 if (i+1 < num && (msgs[i+1].flags == I2C_M_RD)) {
 196                         ret = i2c->fc->i2c_request(i2c, FC_READ, msgs[i].addr,
 197                                 msgs[i].buf[0], msgs[i+1].buf, msgs[i+1].len);
 198                         i++; /* skip the following message */
 199                 } else /* writing */
 200                         ret = i2c->fc->i2c_request(i2c, FC_WRITE, msgs[i].addr,
 201                                 msgs[i].buf[0], &msgs[i].buf[1],
 202                                 msgs[i].len - 1);
 203                 if (ret < 0) {
 204                         err("i2c master_xfer failed");
 205                         break;
 206                 }
 207         }
 208
 209         mutex_unlock(&i2c->fc->i2c_mutex);
 210
 211         if (ret == 0)
 212                 ret = num;
 213         return ret;
 214 }
 215
 216 static u32 flexcop_i2c_func(struct i2c_adapter *adapter)
 217 {
 218         return I2C_FUNC_I2C;
 219 }
 220
 221 static struct i2c_algorithm flexcop_algo = {
 222         .master_xfer    = flexcop_master_xfer,
 223         .functionality  = flexcop_i2c_func,
 224 };
 225
 226 int flexcop_i2c_init(struct flexcop_device *fc)
 227 {
 228         int ret;
 229
 230         mutex_init(&fc->i2c_mutex);
 231
 232         fc->fc_i2c_adap[0].fc = fc;
 233         fc->fc_i2c_adap[1].fc = fc;
 234         fc->fc_i2c_adap[2].fc = fc;
 235
 236         fc->fc_i2c_adap[0].port = FC_I2C_PORT_DEMOD;
 237         fc->fc_i2c_adap[1].port = FC_I2C_PORT_EEPROM;
 238         fc->fc_i2c_adap[2].port = FC_I2C_PORT_TUNER;
 239
 240         strlcpy(fc->fc_i2c_adap[0].i2c_adap.name, "B2C2 FlexCop I2C to demod",
 241                 sizeof(fc->fc_i2c_adap[0].i2c_adap.name));
 242         strlcpy(fc->fc_i2c_adap[1].i2c_adap.name, "B2C2 FlexCop I2C to eeprom",
 243                 sizeof(fc->fc_i2c_adap[1].i2c_adap.name));
 244         strlcpy(fc->fc_i2c_adap[2].i2c_adap.name, "B2C2 FlexCop I2C to tuner",
 245                 sizeof(fc->fc_i2c_adap[2].i2c_adap.name));
 246
 247         i2c_set_adapdata(&fc->fc_i2c_adap[0].i2c_adap, &fc->fc_i2c_adap[0]);
 248         i2c_set_adapdata(&fc->fc_i2c_adap[1].i2c_adap, &fc->fc_i2c_adap[1]);
 249         i2c_set_adapdata(&fc->fc_i2c_adap[2].i2c_adap, &fc->fc_i2c_adap[2]);
 250
 251         fc->fc_i2c_adap[0].i2c_adap.class =
 252                 fc->fc_i2c_adap[1].i2c_adap.class =
 253                 fc->fc_i2c_adap[2].i2c_adap.class = I2C_CLASS_TV_DIGITAL;
 254         fc->fc_i2c_adap[0].i2c_adap.algo =
 255                 fc->fc_i2c_adap[1].i2c_adap.algo =
 256                 fc->fc_i2c_adap[2].i2c_adap.algo = &flexcop_algo;
 257         fc->fc_i2c_adap[0].i2c_adap.algo_data =
 258                 fc->fc_i2c_adap[1].i2c_adap.algo_data =
 259                 fc->fc_i2c_adap[2].i2c_adap.algo_data = NULL;
 260         fc->fc_i2c_adap[0].i2c_adap.dev.parent =
 261                 fc->fc_i2c_adap[1].i2c_adap.dev.parent =
 262                 fc->fc_i2c_adap[2].i2c_adap.dev.parent = fc->dev;
 263
 264         ret = i2c_add_adapter(&fc->fc_i2c_adap[0].i2c_adap);
 265         if (ret < 0)
 266                 return ret;
 267
 268         ret = i2c_add_adapter(&fc->fc_i2c_adap[1].i2c_adap);
 269         if (ret < 0)
 270                 goto adap_1_failed;
 271
 272         ret = i2c_add_adapter(&fc->fc_i2c_adap[2].i2c_adap);
 273         if (ret < 0)
 274                 goto adap_2_failed;
 275
 276         fc->init_state |= FC_STATE_I2C_INIT;
 277         return 0;
 278
 279 adap_2_failed:
 280         i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
 281 adap_1_failed:
 282         i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
 283
 284         return ret;
 285 }
 286
 287 void flexcop_i2c_exit(struct flexcop_device *fc)
 288 {
 289         if (fc->init_state & FC_STATE_I2C_INIT) {
 290                 i2c_del_adapter(&fc->fc_i2c_adap[2].i2c_adap);
 291                 i2c_del_adapter(&fc->fc_i2c_adap[1].i2c_adap);
 292                 i2c_del_adapter(&fc->fc_i2c_adap[0].i2c_adap);
 293         }
 294
 295         fc->init_state &= ~FC_STATE_I2C_INIT;
 296 }